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1.
Plant Cell Physiol ; 63(2): 265-278, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-35166362

RESUMO

The molecular basis for leaf development, a major focus in developmental biology, remains unclear in the monocotyledonous grass, rice (Oryza sativa). Here, we performed a mutant screen in rice and identified an AP2-type transcription factor family protein, NARROW AND DWARF LEAF1 (NDL1). NDL1 is the ortholog of Arabidopsis thaliana (subsequently called Arabidopsis) ENHANCER OF SHOOT REGENERATION1 (ESR1)/DORNRÖSCHEN (DRN) and mediates leaf development and maintenance of the shoot apical meristem (SAM). Loss of function of NDL1 results in bladeless leaves and SAMs that are flat, rather than dome-shaped, and lack cell proliferation activity. This loss of function also causes reduced auxin signaling. Moreover, as is the case with Arabidopsis ESR1/DRN, NDL1 plays crucial roles in shoot regeneration. Importantly, we found that NDL1 is not expressed in the SAM but is expressed in leaf primordia. We propose that NDL1 cell autonomously regulates leaf development, but non-cell autonomously regulates SAM maintenance in rice.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Oryza , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Meristema/genética , Meristema/metabolismo , Mutação/genética , Oryza/genética , Oryza/metabolismo
2.
Plant Cell Physiol ; 63(2): 265-278, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34865135

RESUMO

The molecular basis for leaf development, a major focus in developmental biology, remains unclear in the monocotyledonous grass, rice (Oryza sativa). Here, we performed a mutant screen in rice and identified an AP2-type transcription factor family protein, NARROW AND DWARF LEAF1 (NDL1). NDL1 is the ortholog of Arabidopsis thaliana (subsequently called Arabidopsis) ENHANCER OF SHOOT REGENERATION1 (ESR1)/DORNRÖSCHEN (DRN) and mediates leaf development and maintenance of the shoot apical meristem (SAM). Loss of function of NDL1 results in bladeless leaves and SAMs that are flat, rather than dome-shaped, and lack cell proliferation activity. This loss of function also causes reduced auxin signaling. Moreover, as is the case with Arabidopsis ESR1/DRN, NDL1 plays crucial roles in shoot regeneration. Importantly, we found that NDL1 is not expressed in the SAM but is expressed in leaf primordia. We propose that NDL1 cell autonomously regulates leaf development, but non-cell autonomously regulates SAM maintenance in rice.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Oryza , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Meristema/genética , Meristema/metabolismo , Mutação/genética , Oryza/genética , Oryza/metabolismo
3.
J Immunol ; 203(4): 835-843, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31324723

RESUMO

The cause of systemic lupus erythematosus (SLE) is unknown. IFN-α has been suggested as a causative agent of SLE; however, it was not proven, and to what extent and how IFN-α contributes to the disease is unknown. We studied the contribution of IFN-α to SLE by generating inducible IFN-α transgenic mice and directly show that conditional upregulation of IFN-α alone induces a typical manifestation of SLE in the mice not prone to autoimmunity, such as serum immune complex, autoantibody against dsDNA (anti-dsDNA Ab), and the organ manifestations classical to SLE, such as immune complex-deposited glomerulonephritis, classical splenic onion-skin lesion, alopecia, epidermal liquefaction, and positive lupus band test of the skin. In the spleen of mice, activated effector CD4 T cells, IFN-γ-producing CD8 T cells, B220+CD86+ cells, and CD11c+CD86+ cells were increased, and the T cells produced increased amounts of IL-4, IL-6, IL-17, and IFN-γ and decreased IL-2. In particular, activated CD3+CD4-CD8- double-negative T cells positive for TCRαß, B220, CD1d-teteramer, PD-1, and Helios (that produced increased amounts of IFN-γ, IL-4, IL-17, and TNF-α) were significantly expanded. They infiltrated into kidney and induced de novo glomerulonephritis and alopecia when transferred into naive recipients. Thus, sole upregulation of IFN-α is sufficient to induce SLE, and the double-negative T cells expanded by IFN-α are directly responsible for the organ manifestations, such as lupus skin disease or nephritis.


Assuntos
Interferon-alfa/biossíntese , Lúpus Eritematoso Sistêmico/imunologia , Subpopulações de Linfócitos T/imunologia , Animais , Interferon-alfa/imunologia , Lúpus Eritematoso Sistêmico/metabolismo , Camundongos , Camundongos Transgênicos , Subpopulações de Linfócitos T/metabolismo , Regulação para Cima
4.
Nat Commun ; 10(1): 619, 2019 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-30728357

RESUMO

Axis formation is a fundamental issue in developmental biology. Axis formation and patterning in plant leaves is crucial for morphology and crop productivity. Here, we reveal the basis of proximal-distal patterning in rice leaves, which consist of a proximal sheath, a distal blade, and boundary organs formed between these two regions. Analysis of the three rice homologs of the Arabidopsis BLADE-ON-PETIOLE1 (BOP1) gene indicates that OsBOPs activate proximal sheath differentiation and suppress distal blade differentiation. Temporal expression changes of OsBOPs are responsible for the developmental changes in the sheath:blade ratio. We further identify that the change in the sheath:blade ratio during the juvenile phase is controlled by the miR156/SPL pathway, which modifies the level and pattern of expression of OsBOPs. OsBOPs are also essential for differentiation of the boundary organs. We propose that OsBOPs, the main regulators of proximal-distal patterning, control temporal changes in the sheath:blade ratio of rice leaves.


Assuntos
Padronização Corporal , Regulação da Expressão Gênica de Plantas , Genes de Plantas/genética , Oryza/crescimento & desenvolvimento , Oryza/genética , Desenvolvimento Vegetal/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/genética , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Diferenciação Celular/genética , MicroRNAs/metabolismo , Proteínas Nucleares/metabolismo , Oryza/anatomia & histologia , Oryza/citologia , Fenótipo , Folhas de Planta/anatomia & histologia , Folhas de Planta/citologia , Proteínas de Plantas/genética , Caules de Planta/anatomia & histologia , Caules de Planta/genética , Caules de Planta/crescimento & desenvolvimento , Proteínas Repressoras/metabolismo
5.
Plant Cell Physiol ; 59(2): 376-391, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29272531

RESUMO

In several eudicot species, one copy of each member of the WUSCHEL-RELATED HOMEOBOX (WOX) gene family, WOX1 and WOX3, is redundantly or differentially involved in lateral leaf outgrowth, whereas only the WOX3 gene regulating the lateral domain of leaf development has been reported in grass. In this study, we show that a WOX3 gene, LEAF LATERAL SYMMETRY1 (LSY1), regulates lateral leaf development in a different manner ftom that of other duplicated paralogs of WOX3, NARROW LEAF2 (NAL2)/NAL3, in rice. A loss-of-function mutant of LSY1 exhibited an asymmetrical defect from early leaf development, which is different from a symmetric defect in a double loss-of-function mutant of NAL2/3, whereas the expression of both genes was observed in a similar domain in the margins of leaf primordia. Unlike NAL2/3, overexpression of LSY1 produced malformed leaves whose margins were curled adaxially. Expression domains and the level of adaxial/abaxial marker genes were affected in the LSY1-overexpressing plants, indicating that LSY1 is involved in regulation of adaxial-abaxial patterning at the margins of the leaf primordia. Additive phenotypes in some leaf traits of lsy1 nal2/3 triple mutants and the unchanged level of NAL2/3 expression in the lsy1 background suggested that LSY1 regulates lateral leaf development independently of NAL2/3. Our results indicated that all of the rice WOX3 genes are involved in leaf lateral outgrowth, but the functions of LSY1 and NAL2/3 have diverged. We propose that the function of WOX3 and the regulatory mode of leaf development in rice are comparable with those of WOX1/WOX3 in eudicot species.


Assuntos
Família Multigênica , Organogênese/genética , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Homologia de Sequência de Aminoácidos , Sequência de Bases , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Modelos Biológicos , Fenótipo , Folhas de Planta/citologia , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Reprodução
6.
Neurochem Int ; 51(8): 467-75, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17559977

RESUMO

Activation of ionotropic glutamate (Glu) receptors, such as N-methyl-d-aspartate receptors, is shown to modulate the gene transcription mediated by the transcription factor activator protein-1 (AP1) composed of Fos and Jun family proteins in the brain, while little attention has been paid to the modulation of AP1 expression by metabotropic Glu receptors (mGluRs). In cultured rat cortical neurons, where constitutive expression was seen with all groups I, II and III mGluR subtypes, a significant and selective increase was seen in the DNA binding activity of AP1 120 min after the brief exposure to the group II mGluR agonist (2S,2'R,3'R)-2-(2',3'-dicarboxycyclopropyl)glycine (DCG-IV) for 5 min. In cultured rat cortical astrocytes, by contrast, a significant increase was induced by a group I mGluR agonist, but not by either a group II or III mGluR agonist. The increase by DCG-IV was significantly prevented by a group II mGluR antagonist as well as by either an intracellular Ca(2+) chelator or a voltage-sensitive Ca(2+) channel blocker, but not by an intracellular Ca(2+) store inhibitor. Moreover, DCG-IV significantly prevented the increase of cAMP formation by forskolin in cultured neurons. Western blot analysis revealed differential expression profiles of Fos family members in neurons briefly exposed to DCG-IV and NMDA. Prior or simultaneous exposure to DCG-IV led to significant protection against neuronal cell death by NMDA. These results suggest that activation of the group II mGluR subtype would modulate the gene expression mediated by AP1 through increased intracellular Ca(2+) levels in cultured rat cortical neurons.


Assuntos
Sinalização do Cálcio/fisiologia , Cálcio/metabolismo , Córtex Cerebral/metabolismo , Neurônios/metabolismo , Receptores de Glutamato Metabotrópico/metabolismo , Fator de Transcrição AP-1/metabolismo , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Bloqueadores dos Canais de Cálcio/farmacologia , Células Cultivadas , Colforsina/antagonistas & inibidores , AMP Cíclico/metabolismo , Agonistas de Aminoácidos Excitatórios/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Líquido Intracelular/metabolismo , Neurônios/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/fisiologia , Proteínas Proto-Oncogênicas c-fos/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos , Ratos Wistar , Receptores de Glutamato Metabotrópico/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/fisiologia
7.
J Invest Dermatol ; 127(7): 1745-51, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17344931

RESUMO

POLH mutations were identified in 16 Japanese patients, who were diagnosed, both clinically and at a cellular level, as being of the xeroderma pigmentosum variant type (XPV). While all the patients developed skin cancer with an average onset of the cancer at 45 years, in non-XP Japanese the onset was at over 70 years. All the cell strains from the patients were normal or slightly hypersensitive to UV and most of these showed enhanced UV sensitivity when the post-UV colony formation was performed in the presence of caffeine. Immunoprecipitation analysis with two kinds of anti-POLH protein antibodies revealed that cells from 13 patients did not show the 83 kDa POLH band and that cells from one patient had a faint 83 kDa band. All of these 14 cell strains, without a POLH band or with a weak POLH band, had mutations in the POLH gene. The IP analysis of the POLH protein revealed a very useful method for screening the patients suspected of XPV. Seven mutations in the POLH gene including three novel mutations were identified. Among the mutations detected, 11 alleles out of 28 (39%) were G490T mutations.


Assuntos
Povo Asiático/genética , DNA Polimerase Dirigida por DNA/genética , Mutação/genética , Neoplasias Cutâneas/genética , Xeroderma Pigmentoso/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Estudos de Casos e Controles , Células Cultivadas , DNA de Neoplasias/metabolismo , DNA de Neoplasias/efeitos da radiação , DNA Polimerase Dirigida por DNA/metabolismo , Feminino , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Testes Genéticos/métodos , Humanos , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Pele/enzimologia , Pele/patologia , Raios Ultravioleta
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